This invention relates to fastening, and more particularly to methods and apparatus for the fastening of biological tissues.
A method of joining biological tissue is shown in U.S. Pat. No. 3,086,208. A U-shaped clip having barbs is applied to folded tissue layers, as for the closing of incisions. A feature of the installed clip is that it juts out from the joined area. This can be disadvantageous for fastening internal tissues because the clip could extend into interstitial areas between the fastened tissue and adjacent tissues. Thus irritation can occur, or the clip can be worked loose causing evisceration. Moreover, numerous clips must be employed for high strength fastening, due to the small area over which force is applied.
Another fastener used in joining tissues has the form of an adhesive strip. The strip extends across an incision, thus holding the wound closed. A limitation of this device is that it is not appropriate for the fastening of internal structures. Further, the fastener lacks sufficient strength for high stress applications.
One of the most common tissue fasteners are thread sutures. These fasteners are installed by sewing the suture through the structures to be fastened. A disadvantage to sutures lies in the relatively great amount of time required for installation. Installation delays result in high operating room costs and increased patient trauma. Moreover, while these sutures may be installed in biodegradable (dissolvable) form, they dissolve fairly rapidly, making their use unsuitable in applications where fastening strength must be maintained over longer time periods.
Thus, it is an object of the invention to provide a fastener which is rapidly installed and which renders high initial levels of fastening strength. (tensile strength)
It is an additional object to provide a fastener and installation apparatus which may be used for internal application, without requiring extensive surgery.
It is a further object of the invention to provide a fastener which is biodegradable, yet maintains high fastening strength over a relatively longer time period than known fasteners.
It is yet another object of the invention to provide a fastener which becomes firmly anchored in the fastened structures and avoids protuberances into neighboring interstitial areas.